Synthesis of Ce~(3+) doped SrS nanocrystalline phosphors using a simple aqueous method

摘要

A simple aqueous method was used to synthesize a blue-green emitting Ce~(3+) doped SrS nanocrystalline phosphor. SrCl_2, Na_2S_2O_3 and Ce(NO_3)_3 were used as precursors for Sr~(2+), S~(2-) and Ce~(3+) ions respectively. Ethlylene diamine tetra acetic acid (EDTA) was used as a complexing agent. XRD studies revealed the single crystalline phase of the SrS:Ce~(3+). The morphology was examined using SEM and TEM and average particle size estimated from TEM images was 25 ± 2 nm in diameter. The elemental composition was analyzed with the electron dispersive x-ray spectroscopy (EDS). The photoluminescence (PL) study showed two emission peaks at 480 nm and 527 nm ascribed to the ~2D(5d)→~2F_(5/2)(4f) and ~2D(5d)→ ~2F_(7/2)(4f) transitions of the Ce~(3+) ion in SrS:Ce nanophosphors. These peaks are blue shifted from bulk SrS:Ce peaks at 485 nm and 530 nm. The intense emission peak at 480 nm at 254 nm excitation may be explored for possible applications in gamma and x-rays scintillators.